Security guards who remain on the work site 16 hours per day during the week (eight hours "on duty" and eight hours "on call") and 24 hours per day on the weekends (16 hours "on duty" and eight hours "on call") must be compensated for their "on call" time; but

The employer could deduct up to eight hours of regularly scheduled "sleep time" when the trailer guards worked 24 hour shifts because the employer and trailer guard employees had entered into an agreement to exclude eight hours of sleep time from the guards' compensable time.

The California Supreme Court granted review on 10/16/13. Mendiola is Case No. S212704, and the Court's web page for it is here.